Abstract: Apparatus that removes solids from a liquid by flotation and by sedimentation has a uniform surface distribution of small bubbles for making solids float. Large bubbles which would cause turbulence and uneven bubble flow are confined and eliminated.

Abstract: An improved apparatus for purifying a liquor containing biodegradable wastes wherein the liquor is delivered serially to a number of zones. The liquor is first delivered to a clarification zone to remove suspended solids, and is then delivered to an oxidation/nitrification zone where the liquor is subjected to oxidation by aerobic microorganisms. The liquor is next delivered to a denitrification zone, where it is subjected to the action of anaerobic bacteria. Both the oxidation/nitrification zone and the dentrification zone contain a particular type of submerged media which comprises a multiplicity of elements freely and randomly stacked on one another to provide interstitial area therebetween. The elements have a high surface area to volume ratio in order to promote the growth of microorganisms.

Abstract: A process for scrubbing undissolved impurities from the upper portion of an ion exchange resin filtration bed is disclosed wherein air is introduced in the upper portion of the bed and develops a pressure within the vessel. This pressure subsequently forces rinse water down through the upper portion of the bed and out of the vessel. The gas is introduced into the bed and the water is drained therefrom at a level below the bed's upper surface but above a substantial lower portion of the resin bed. In this manner, lesser quantities of scrubbing fluids are required and the majority of the resin material is left undisturbed to maintain maximum ion exchange capacity.

Abstract: The liquid deflecting surface of a conical baffle of a spray nozzle is defined by an arc of a circle rotated around the central axis of the nozzle, and a single supporting arm for the baffle has a knife-like edge that merges into the point of such conical surface.

Abstract: A method for recovering and reusing liquid used to backwash a precoated filter in which the backwash liquid used in a previous backwashing cycle is passed through a filter that is about to be backwashed. The used backwash liquid is treated by the remaining capacity in the filter precoat, and is then used to backwash the filter. This backwash liquid is recovered for later treatment and use in another backwashing cycle.

Abstract: A spray nozzle with a discharge surface defined by the formula X = .+-. 0.875D-t-0.5y- .sqroot.0.75Dy, with D being the outside diameter of a connected heat exchanger tube, and t being the thickness of such heat exchanger tube, does not create sufficient back pressure to destroy the thin film layer of liquid flowing down the inside of such heat exchanger tube.

Abstract: Apparatus in the shape of a parallelogram for separating solids from liquids consisting essentially of parallel tubes tilted toward one end of the parallelogram made by bonding square-tooth members extending across the width of the parallelogram to flat sheets that also extend across the width of the parallelogram.

Abstract: A drift eliminator assembly for a liquid cooling tower employs deformable resilient drift eliminator blades which snap into mounting slots and are held in place without fasteners or a bonding agent.

Abstract: An improved method for precoating a filter with a mixture of anion and cation exchange resin particles in the size range of about 60 to 400 mesh is provided, wherein a floc of anion and cation exchange resins is formed by mixing these resins in aqueous suspension at elevated temperatures in the range of about 100.degree. to 212.degree. F. and coating these resins onto a filter.

Abstract: An improved sealing means for securing a fin tube heat exchange element to the floor of a heat exchanger or cooling tower hot water basin. The sealing means includes a first collar section received around the fin tube and a second collar section received around an opening in the hot water basin floor. A compliant web section connects together the first and second collar sections. Gusset reinforcement members are provided to the web section to reduce twist and prevent seal leakage. Small circumferential grooves are provided in the portion of the second collar section which seals against the basin floor to effect a positive seal. The opening in the basin floor is large enough to permit the effortless vertical extraction of the fin tube element.

Abstract: A method and apparatus for stripping ammonia from an alkaline regenerant solution used for the regeneration of a zeolite ion exchange bed. The regenerant passes through a stripping column. An acidic working solution is circulated from a holding tank through a vacuum creating means and then back into the holding tank. The ammonia is stripped from the regenerant under a vacuum created in the stripping column by the vacuum creating means so as to cause the stripped ammonia to chemically react with working solution to form an ammonium salt solution. Carbon dioxide free air is passed upward through the column countercurrent to the flow of regenerant.

Abstract: A flow control nozzle for directing a liquid through the floor of a liquid containing basin which includes: a substantially vertical tubular portion having a lower end adapted to extend through the floor of the basin; a chamber portion having a bottom surface adapted to communicate with an upper end of the tubular portion, the bottom surface having openings formed therethrough and being positioned a predetermined distance above the floor of said basin so as to permit liquid to pass therethrough into said chamber portion; and an air vent tube having an upper end adapted to communicate with the atmosphere and a lower end adapted to communicate with said tubular portion.

Abstract: An improved aeration apparatus for use in sewage treatment plants to dissolve oxygen into the sewage. The aeration apparatus is specifically designed for use in combination with a single home sewage treatment unit. The aeration apparatus includes a motor assembly for rotation of a propeller through a downwardly extending drive shaft. The propeller extends downwardly into a draft tube so as to pump the liquid to be aerated upward therethrough. A deflector plate directs the rising liquid radially outward in all directions. A slinger is positioned about the drive shaft immediately below the deflector plate. The motor is designed to pull only fresh air into the aerator housing. To avoid clogging the propeller is free to move in one direction or another when a large object comes through the draft tube.

Abstract: An improved method and apparatus for treating liquor containing biodegradable wastes wherein the liquor is first delivered to a quiescent settling zone and then to an aeration zone. The aeration liquor is delivered downwardly through a column of submerged fixed media having a high surface area to volume ratio so that aerobic microorganisms can grow on their surface. The liquor is recirculated through the aeration zone and fixed media, and is withdrawn from the unit after treatment.

Abstract: Methods and apparatus are disclosed for treating biodegradable waste products. A liquor of waste products is introduced into a reactor mixing zone comprising a column of fixed media material having a high surface area to volume ratio, a low resistance to liquid flow and a surface condition receptive to aerobic microbial growth. The liquor is circulated in a continuous flow path including the fixed media column. Preferably, a mechanical surface aerator is positioned in the continuous flow path immediately above the mixing zone to aerate the liquor and distribute it uniformly over the top of the fixed media column. The aeration, distribution and circulation of the liquor are accomplished in a manner to promote homogeneous mixing throughout the mixing zone and to encourage aerobic microbial growth on the fixed media while minimizing agitation of a nature tending to dislodge the aerobic microbial growth from the fixed media and develop flocculent aerobic microbes.

Abstract: A sludge removal system for use in the removal of settled sludge collected on the bottom surface of a circular clarifier. The system includes a plurality of self-supporting sludge receiving conduits of various lengths extending radially outward from the center of the tank in a common horizontal plane. Each conduit has a sludge pick-up port associated with the outer end thereof. Vertical riser tubes extend upward from the inner ends of the conduits into a sightwell assembly. At the upper end of each riser tube is a flow control valve arrangement to regulate the amount of sludge flow through each conduit. The valve indicates a pipe within a pipe, both pipes having slotted openings cut therefrom, to provide a variable flow orifice the size of which may be controlled by rotating the inner pipe about the stationary outer pipe. The upper edges of the slotted openings extend above the static liquid level in the clarifier.

Abstract: Apparatus for feeding the raw influent water into a center post clarifier including an uptake zone defined around the center post forming an eductor tube having an upper and lower end respectively in communication with an upper and lower portion of the mixing and recirculation chamber. A first set of openings is provided intermediate the center post for directing the flow of raw water upwardly into an intermediate portion of the uptake zone. A second set of openings positioned above the first set of openings is provided for directing the remaining flow of raw water from the center post into an upper portion of the uptake zone. The relative flow rates of raw water through the first and second openings being such as to cause sludge which has accumulated adjacent the lower end of the uptake zone to be lifted therein to and recirculated with the raw water. Means are provided to selectively control the flow rates of raw water through the first and second openings to adjust the sludge recirculation rate.

Abstract: A horizontally elongated container for an underground equipment installation which includes a flat floor and ceiling along with semi-cylindrical end shells. The container is reinforced by rigid-frame beam rings around a flat-sided center section.

Abstract: A brine system to manufacture brine for the regeneration of ion exchange material including a brine well positioned within a brine drum. A vertically adjustable air chamber activates a diaphragm and control arm assembly which in turn controls inlet shut-off valves associated with the brine well when the water level within the drum reaches a predetermined level. The control arm has a unique cam arrangement associated therewith which prevents premature shut-off of the valves. Water enters and is withdrawn from the brine well through a down tube having a vertically adjustable lower end extending down into the brine well to a predetermined level and an upper end in communication with the shut-off valves through a series of passageways and chambers. A floating disc seal is provided within one of these chambers to shut-off the air entering the chamber after the brine is drawn down to a level below the lower end of the down tube.

Abstract: A grit selector having an upper settling chamber and a lower grit storage chamber. The settling chamber communicates with the storage chamber through a relatively small opening in a flat transition surface therebetween. Rotating paddles critically positioned within the settling chamber cause the flow of liquid entering the settling chamber adjacent the outer periphery to rotate about the chamber in a forced vortex having upward spiral flow. Settled grit attaches to the transition surface at the settling chamber perimeter before one revolution. The spiral flow urges the grit across the transition surface towards the opening while the organics are lifted upward and back into the flow. The grit drops through the opening into the grit storage chamber and the organics are carried out of the settling chamber through an outlet passageway.